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Copyright of Tianjin Medical Journal is the property of Tianjin Medical Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Carsologica Sinica is the property of Institute of Karst Geology, CAGS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Carsologica Sinica is the property of Institute of Karst Geology, CAGS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of Soil & Water Conservation is the property of Bulletin of Soil & Water Conservation Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Yellow River is the property of Editorial Board of Yellow River and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The problem of disrupted flight recovery is a very complicated real-time network optimization problem, which belongs to NP-hard problem. Considering the situation caused by the shortage of aircraft resources, the closure of airports and the unplanned maintenance, this paper adopts multiple recovery options, such as flight delays, flight cancellations, flight swaps and so on. Based on Dantzig-Wolfe decomposition principle, the mathematical optimization models of master problem and sub-problem are established respectively. And column generation algorithm is introduced to solve this large integer programming problem. In the solving process, first, the initial feasible routes are constructed and the master problem is solved with CPLEX software based on the lines. Secondly, in view of the characteristics of the problem, some properties are proposed, then the sub-problem is solved by using the improved "label-setting algorithm", and in each iteration, multiple columns with reduced cost are added to reduce the number of iterations, then the branch and bound algorithm is used to handle the non-integer solutions. Finally, the correctness and efficiency of the method are verified by testing the practical instances of various scales, and the test results are analyzed and summarized. [ABSTRACT FROM AUTHOR]

The present paper is to study the relationship between vegetation and groundwater, and the constrains on coal mining in ecologically fragile mining area. A field survey was carried out to determine the general rules of vegetation community succession, along with the increase of depth to groundwater table (DGT) in a typical region. Based on the remote sensing data and DGT data before mining, a statistical relationship between the normalized difference vegetation index (NDVI) and DGT was established in Yushenfu coal mining area. The results showed that the vegetation has a zonal characteristic as DGT increasing,and the most suitable DGT for vegetation is 0-4.0 m, the smaller the DGT, the more sensitive the vegetation. Combined with the hydrological condition and the relationship between vegetation and groundwater, the Yushenfu coal mining area could be divided into three parts: vegetation constraint region, groundwater constraint region and non-constrained region. It is in the vegetation constraint region that coal mining will cause extensive damage to vegetation. As the DGT dramatically declined, the NDVI improved in large extent by 2014, to some extent, this was due to the present mining mainly located in non-constrained region. Mine planning and coal mining must pay attention to the relationship of vegetation and groundwater in ecologically fragile mining area. [ABSTRACT FROM AUTHOR]

It is universally acknowledged that phreatophytic transpiration changes sensitively with groundwater level declining. The present study tries to find the groundwater level decline threshold limited to the vulnerable ecological conditions at Yushen mine. The methods include in-situ test and numerical analysis, firstly an experimental base was constructed for collecting data, including meteorological factors, soil moisture, groundwater level and Salix psammophila transpiration, then a root water uptake model was derived to simulate the change of Salix psammophila transpiration during groundwater level declining. The results show that：Salix psammophila transpiration is strictly controlled by meteorological factors, there appears two extremums before and after 12 noon, and Salix psammophila transpiration changes more sharply with a shallow groundwater level. The contribution rate of groundwater to evapotranspiration declines with the groundwater depth goes deeper, which decrease from 100% to 0 with groundwater depth decreasing from 15 cm to 215 cm. Salix psammophila cannot utilize groundwater when the groundwater depth is more than 215 cm, that is the threshold of groundwater level decline limited to the vulnerable ecological conditions during coal mining in the study area. The results achieved above will enrich the coal mining technology at ecologically vulnerable coal mine. [ABSTRACT FROM AUTHOR]

Coal mining has great influence on the groundwater dynamic in the blown-sand region of the northern Shaanxi Province. On the basis of long-term monitoring data of groundwater table，the change characteristics of Salawusu group unconfined groundwater table regional dynamic from time and space in Yuyang district of Yulin City were analyzed comprehensively. Dynamic types of shallow groundwater table in the study area were classified into three types by Interactive Self-Organizing Data Analysis Technique (ISODATA)：the strong fluctuation area of groundwater table (Type Ⅰ)，the medium fluctuation area of groundwater table (Type Ⅱ) and the weak fluctuation area of groundwater table (Type Ⅲ). The change laws and main influence factors of groundwater table in different dynamic type areas were analyzed and the correlation analysis between groundwater table dynamic and coal mining and atmospheric precipitation was carried out. The conclusion is that the groundwater table dynamic in Type Ⅰ area，which presents a stronger fluctuation，is mainly affected by atmospheric precipitation，while the groundwater table dynamic in Type Ⅱ and Ⅲ is weaker because of the comprehensive influence of atmospheric precipitation and coal mining. Under the present mining conditions，the main influence factor of regional groundwater dynamic in the study area is atmospheric precipitation，followed by coal mining. [ABSTRACT FROM AUTHOR]